A board to board electrical connector is often surface mounted on a printed circuit board by soldering. Pertinent examples are disclosed in U.S. Pat. Nos. 5,681,174 and 5,697,799 and in Taiwan patent application Nos. 84105863, 85103740, 85103743 and 86202873.
Referring to FIG. 6, a conventional electrical connector 100 comprises an elongate housing 102 and a plurality of contacts 104 received in the housing 102. The housing 102 includes two opposite thin sidewalls 105. Each contact includes a fixing portion 106, a mating portion 108 upwardly extending from an end of the fixing portion 106 and a soldering portion 110 perpendicularly extending from an opposite end of the fixing portion 106 for being surface mounted on a printed circuit board 112.
However, since the soldering portion 110 perpendicularly extends from the fixing portion 106, during the soldering procedure, molten solder easily wicks toward the fixing portion 106 thereby adversely affecting reliability of the solder connection. Furthermore, since each side wall 105 of the housing 102 is elongate and thin, during an ejection molding procedure and the soldering procedure, the side wall 105 is easily deformed as exposed to high temperature gradient.